#include <iostream>
#include <cmath>

using namespace std;

double fun(double a, double b, double *sqab,double *lnab,double *avg)
{
    *sqab=a*a+b*b;
    *lnab=log(a)+log(b);
    *avg=(a+b)/2;

    return(sqrt(a+b));
}

int main ()
{
    double x=10,y=12,fsq,fln,favg,fsqr;
    fsqr=fun(x,y,&fsq,&fln,&favg);
    cout<<"x="<<x<<"  y="<<y<<"  fsq"<<fsq<<"  fln="<<fln<<"  favg="<<favg<<"  fsqr="<<fsqr<<endl;
    
    cin>>x;
    return 0;
}